Pneumatic gun



March 30, 1954 w G, SHERMAN ET A1.

PNEUMATIC GUN Filed Oct. 30, 1950 Patented Mar. 30, 1954 PNEUMATIC GUN Wilbur G. Sherman and San Diego,

Charles E. Colling, Calif.

Application October 30, 1950, Serial No. 192,875

12 Claims. l

Our invention relates to a pneumatic gun, and more particularly to a pneumatic gun having novel air-releasing valve mechanism, and the objects of our invention are:

First, to provide a pneumatic gun of this class having an air release valve` which is opened by air under pressure which passes from the pressure chamber into the barrel of the gun;`

Second, to provide a pneumatic gun of this class having a novel toggle-operated sear engaging a pressure-operated valve, whereby exhaustion of pressure byv ysaid valve into the barrel of the gun permitS-springsin connection with said toggle-operated sear to return said valve to closed position automatically;

Third, to* provide a pneumatic gun of this class having novel valve means which expo-ses the entire periphery of the rear end of the gun 1barrel to air pressure, whereby very rapid release of air from the air chamber to the breech of the barrel is accomplished;

Fourth, to provide a pneumatic gun of this class which does not require any cooking oi valve-releasing plungers during the operation thereof;

Fifth, to provide a pneumatic gunc-f this class which is readily adapted to operate with very high pressures;

Sixth, to provide a pneumatic, gun or" this class having valve means which is adapted to operate at very high pressures, due to the thrust dinerential on the valve by yair pressurenvhich tends'to open the valve with a certain amount oi force proportional to the pressure of air in the air chamber;

Seventh, to provideI a pneumatic gun of this class which is readily adapted for ulsein propelling projectiles by means of `dry ice expansion, or by any other suitable high-pressure gas;

Eighth, to provide a pneumatic gun of this class in which the trigger pull may be very light and smooth, and in which moving mechanism during the shooting thereof ispredominantly axialof the barrel, whereby extreme accuracy is promoted;

Ninth, to provide a pneumatic gun of this class having a valve means which exposes the entire periphery oi the breech endfof the barrel to air pressure, causing uniform propelling action on the projectile in the barrel, which greatly promotes accuracy;

Tenth, to provide a pneumatic gun of this class having valve means which subjects the projectile in the barrel to the optimum pressure very quickly, whereby the maximuml velocity of the projectile proportional to= they air pressure and volumetric displacement of the chamber is attained; and

Eleventh, to provide a pneumatic gun of this class which is very simple and economical of construction, efcient in operation, and which will not readily deteriorate or get out of order.

With these and other objects in view, as will appear hereinafter, our invention consists of certain novel features of construction, combination and arrangement of parts and portions, as will be hereinafter described in detail and particularly set forth in the appended claims, reference being 'had to the accompanying drawings and to the characters of reference thereon, forming a part of this application, in which:

Fig. 1 is a fragmentary sicle'elevational view of our pneumatic gun, showing portions broken away and in section on a substantially vertical plane through the axis of the gun; Fig. 2 is a fragmentary sectional view, taken from the line 2-2 of Fig. 1; Fig. 3 is ya fragmentary sectional view, taken from the line 3-3 of Fig. l; Fig. 4 is a transverse sectional vie taken from the line 4--4 of Fig. 3; Fig. 5 is a fragmentary sectional view onl the same plane as. the structure shown in section in Fig. 1 of the dra-wings', illustrating thevvalve of the pneumaticy gun in open position, and the toggle sear mechanism pivoted backwardly; and Fig. 6 is a fragmentary sectional view of a modied form of the mechanism showing a gas chamber adapted to supply carbon dioxide gas or the like to the valve of the gun.

Similar characters of reference refer to similar parts and portions throughout the several views of the drawings.

The barrel l, valve cas-ing 2, valve member 3, cushion Il, sealing rings 5, S, l and 8, bullet-seating bolt 9, bolt handle l0, se'ar l l, toggle IE, pins i3 and I4, toggle stop it?, toggle springs l5 and i1, trigger i8, trigger spring I9, adjusting screw 2li, trigger guard 2l, stock 22, pump plunger 23, check valve 2li, spring 25, and the plug 26, constitute the principal parts and portions of our pneumatic gun.

The barrel l of our pneumatic gun is provided with a bore la which may be rifled or may be adapted to shoot shot, orother projectiles as desired. The barrel l is provided with a pump cylinder lb connected therewith, in which a conventional pump plunger 23 is reciprocally mounted, which communicates through an oriiice le with the check valve 2li, held by the spring 25, which is abutted to the plug 2B. Communicating with the check valve 24 is an air passage Id, which extends rearwardly to the vent portion le thereof. This vent portion ic is positioned lat a reduced outside diameter portion if of the barrel l, on which the forward end 3a ci the valve member 3 is slidably mounted.

This end portion 3a, of the valve member 3 is provided with an annular groove in which the resilient sealing ring 5 is positioned. This resilient sealing ring Si traverses and seals upon the reduced in diameterportion if of the barrel I. Integral with the reduced diameter portion I f is a further reduced outside diameter portion Eg, on which the rear end portion 3b of the valve member 3 is slidably mounted. It will be noted that the further reduced in diameter portion ig provides for a pressure diierential area between opposite ends cf the valve member 3 when gas is under pressure therein, causing a tendency of the valve member 3 to move rearwardly toward the cushion fi, which is held within the valve casing 2.

The sealing ring 6 is positioned in an annular o groove externally of the reduced in diameter portion Ig, and is engaged by the slidable rear end portion 3b of the valve member 3. This sealing ring 6 is near the rear open end lh of the barrel I, all as shown best in Fig. l of the drawings.

The valve casing 2 is a hollow cylindrical. casing having a screw-threaded portion 2a, screwthreaded on the barrel l and extending slightly forwardly of the reduced dia-meter portion if of the barrel I. the annular hollow cylindrical valve 3, which is considerably larger in internal diameter than the external diameter of the reduced'barrel portion I f, providing an air chamber within said valve member 3, which at all times communicates with the opening Ie of the passage Id, as hereinbefore described. The rear end of the valve member 3 is provided with an inwardly disposed end portion 3b, which is an elongated sleeve structure adapted to overlap the Vrear end portion Ih of the barrel I, and the forwardly extending hollow cylindrical portion 2b of the valve casing 2.

This hollow cylindrical portion 2b is substantially identical in diametrical measurement with the reduced barrel portion Ig. and the bore Ia of the barrel I. The bullet-seating bolt 9 is slidably mounted longitudinally in the internal bore of the hollow cylindrical portion 2b of the valve casing 2, and is engaged by the sealing ring S therein. It will be noted that the sealing rings G and 'I on the portions I g and 2b, respectively, are engageable with the portion 3b of the valve member hereinbefore described.

It will be noted that the cushion i is positioned r rearwardly of the valve member 3, within the valve casing 2, and is adapted to stop the rearward movement of the valve member E, when the forward edge 3c of the hollow cylindrical portion 3b of the valve member 3 moves back.- ward into substantially flush position with the forward end of the hollow cylindrical portion 2b of the valve casing 2.

The bullet-seating bolt 9 is provided with a small diameter punch at its forward end, adapted to force a bullet, as indicated by dash lines A, into the bore Ia of the barrel I. Extending through the bullet-seating bolt i) is the pin 9b, which also extends into the bolt handle It,

and is slidably mounted in a slotted portion 2c in the hollow cylindrical portion 2b of the valve casing 2, all as shown best in Figs. l and 3 of the drawings. This slotted portion 2c is provided with a straight narrow slotted portion 2d and an offset portion 2e, providing a shoulder 2f This valve casing 2 surrounds n on which the pin 9b may be locked for holding the bullet-seating bolt 9 forwardly in the position as shown in Fig. 1 of the drawings. The offset portion 2e is also wide enough to receive a bullet A, which may be loaded into the bore when the bullet-seating bolt 9 is rearwardly of said portion 2e of said slot 2c.

Fixed to the valve casing 2 is a downwardly extending arm 2g, through which the pin I4 extends, pivotally mounting the trigger I8 and the toggle member I2 thereto. Pivotally mounted on the toggle member I2 by means of the pin I3 is the sear II. This sear II is provided with a sharp end portion IIa, engaging the annular groove 3d of the valve member 3, all as shown best in Figs. 1 and 5 of the drawings. Screwthreaded in the toggle member I2 is an adjusting screw I2a, engageable with the sear II for adjusting the over-center relationship of the pin I3 relative to the pin Irl and the end portion Ila of the Sear II.

The trigger I8 is provided with a toggle-engaging arm portion Isa which engages the upper side of the toggle member I2 for forcing the same downwardly and causing the pin I3 to pass over-center relative to the pin I4 and the end I Ia of the sear II. Fixed to the arm 2g, extending downwardly from the valve casing 2, is the screw 2d on which the spring I9 is positioned, held in adjustment by the nut 20a. This spring I9 tends to hold the trigger IS forwardly against the arm 2y and the tension of this spring may be adjusted by means of the nut 20a to vary the pull weight of the trigger, as desired.

The toggle stop I5 is provided with a cushionl Ita, adapted to stop the rearward travel of the toggle I2 when ythe toggle structure of the sear II and toggle I2 is broken by pulling the trigger I3. The springs I6 and I1 are secured at their rear end portions to the pin I2b on the toggle member I2, and are secured attheir forwardA ends to the pin I5b on the toggle stop I5. These springs I6 and I'I, at opposite sides of the toggle I2, are tension springs tending to force the searY II and toggle I2 forwardly into the solid line position, as shown in Fig. 1 of the drawings, wherein the sear II holds the valve member 3 forwardly, and in which the pin I3 isV in overcenter position relative to the pin I4 and the end IIa of the sear II.

The operation of our pneumatic gun is substantially as follows:

When it is desired to propel the bullet A through the bore Ia of the lbarrel I by compressed air, the operator operates the conventional pump plunger 23, forcing air through the orifice Ic, past the check valve 24 and into the passage Id, frornwhich it is exhausted at the terminus Ie into the interior of the valve member 3, inter- 'l mediate the sealing ring 5 and the sealing ring 8. When sufficient air has been compressed into the interior of the valve member 3, the bolt handle I maybe turned in a counter-clockwise direction, releasing the pin 9b from the shoulder 2f. Then the bolt handle Id may be pulled backwardly until the pin Sb has traversed the full length of the portion 2d of the slot 2c. At this position, the punch 9a of the bullet-seating plunger 9 is disposed rearwardly of the enlarged portion 2e of the slotted portion `2c of the valve casing 2. l

A bullet may be inserted in said enlarged portion 2e of the slot 2c and subsequent closing of thebolt 9 into the position as shown in Fig. l

' of the drawings seats the bullet in the rear end of the boro Ia, substantially flush with the rear end Ih thereof. When the bolt handle I is forced forwardly to the position as shown in Fig. 1l of the drawings; it is rotated in a clockwise direction until the pin 9b is locked on the shoulder 2f; as shown in Fig. 3 of the drawings, firmly supporting the bullet-seating bolt 9 in the position shown in Fig. 1, wherein the punch portion 9a only projects intermediate the rear end Ih of the barrel I, and the forwardly extending end 2b ofthe hollow cylindrical portion within the valve casing 2. The O-ring 8 seals the periphery of the bullet-seating bolt 9 within the valve casing 2, while the sealing rings 6 and I seal the rearward portion of the valve member 3 against loss of' compressed air therein.

When the trigger I8 is pulled, it is resisted by compression of the spring I9, and pivots on the pin I4, causing the arm I8a to engage the toggle I2, forcing the pin I 3 over-center relative to the pin I 4 and the end IIa of the sear I I, which permits compressed air within the valve member 3 to force the valve member 3 backwardly against the cushion 4 until the forward edge 3c of the portion 3b substantialy coincides with the front end 2b of the hollow cylindrical portion of the valve casing 2, hereinbefore described. Compressed air then rushes into the rear end I h of the bore la of the barrel I, around the entire periphery thereof, which propels the bullet longitudinally of the bore la.

As soon as the air is exhausted from the valve member 3, springs I6 and Il' force the toggle I2 and' sear I`I upwardly into the position as shown in Fig. l of the drawings, carrying the valve member 3 to the solid line position as shown in Fig. 1, wherein it is again ready to be charged with compressed air, it being noted that the over-center pin I3 locks the valve member 3 in this position until released by the trigger I 8.

The diametrical differential between the reduced diameter barrel portions If and Ig provides for a cross-sectional area dierential between the forward and rearward ends of the valve member 3 at its interior, tending to force the member 3 backwardly toward the cushion 4 when compressed air is introduced through the opening IeV of the passage Id.

It will be noted that when the valve member 3 moves backwardly, carrying the sear II and toggle I2 into the position as shown in Fig. 5 of the drawings, the toggle I2 engages the cushion I 5a of the toggle stop I5, effectively preventing displacement of the end IIa of the sear II from the annuar groove 3d in which it is continuously engaged.

In the modification as shown in Fig. 6 of the dra-"'ings, the bore 21 corresponds to the bore Ib, but is used for containing a charge of Dry Ice. At the outlet of this bore 2l is a metering orice member 28, having a line orifice 23a therein which communicates with a passage 3c, corresponding to the passage Id hereinbefore described. In operation, Dry IceV maintains the continuous pressure of substantially eight or nine hundred pounds per square inch in the bore 2i', and passes through the metering orifice 28a into the interior of the va`ve member 3. Each time the trigger I8 is pulled and the valve member 3 moves backwardly, as hereinbefore described, the springs I6 and Il return the valve member 3 to its forward position as shown in Fig. 1, as soon as the pressure decreases sufficiently. The slow meteringV of carbon dioxidegas from the Dry Ice in connection therewith i" cation, we do not through the opening 28a prevents the gasy from building up suiiicient pressure within the valve member 3 to resist the action of the springs I6 and I7 in moving the valve member 3 forwardly until the over-center pin I3 is in proper position.

It will be noted that the time required for the placement of a bullet in the bore Ia, as hereinbefore described, is suflicient for the passage of a proper amount of gas through thev orice 28a to build up an optimum pressure within the valve member 3.

Though we have shown and described a particular construction, combination and arrangement of parts and portions, and a certain modiwish to be limited to this particular construction, combination and arrangement, but desire to include in the scope of our invention the construction, combination and arrangement substantially as set forth in the appended claims.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

l. In a pneumatic gun, a barrel having a bore therein, a source of compressed air, a valve member slidable on said barrel, the entire cross-sectional area of said bore exposed to said valve member, and means creating a pressure area differential directly on said valve tending to open the same for exposing the entire open rear end of said bore to said source of compressed air, about the entire cross-sectional area of said bore, a spring for returning, said valve to closed position when the pressure within said source of compressed air is lowered, said spring action for returning said valveV to closed position being automatic.

2. In a pneumatic gun, a barrel having a bore therein, a source of compressed air, a valve member slidable on said barrel, the entire cross-sectional area of said bore exposed to said valve member, and means creating a pressure area differential directly on said valve tending to open the same for exposing the entire open rear end of said bore to said source of compressed air, about the entire cross-sectional area of said bore, a spring for returning said valve to closed position when the pressure within said source of compressed air is lowered, said spring action for returning said valve to closed position being automatic, a sear directly engaging said valve member for releasing the same and permitting said cross-sectional area pressure differential to move said valve to open position.

3. In a pneumatic gun, a barrel having av bore therein, a source of compressed air, a valve member slidable on said barrel, the entire cross-sectional area of said bore exposed to said valve member, and means creating a pressure area differential directly on said valve tending to open the same for exposing the entire open rear end of said bore to said source of compressed air, about the entire cross-sectional area of said bore, a spring for returning said valve to closed position when the pressure within said source of compressed air is lowered, said spring action for returning said valve to closed position being automatic, a sear directly engaging said valve member for re'easing the same and permitting said cross-sectional area pressure differential to move said valve to open position, toggle means on said sear for holding said valve member closed.

4. In a pneumatic grn, a barrel having a bore therein open at both ends, a valve slidably mounted on one end ofv said barrelv and having cross-sectional area pressure diierential means, a source of compressed air communicating directly with said valve thereby to provide communication between said source of compressed air and said barrel by way of a direct passage, tending to open said valve and expose the entire crosssectional area of one open end of said barrel to said source of compressed air, a spring for automatically closing said valve and shutting off communication with said source of compressed air and the one open end of said bore when pressure of said compressed air is reduced to a predetermined value.

5. In a pneumatic gun, a barrel, a hollow cylindrical valve member slidable externally of said barrel and larger in internal diameter than the external diameter of said barrel, a diametrical step portion in said barrel intermediate opposite ends of said valve member, means for sealing opposite ends of said valve member engaging said barrel, said barrel open near one end of said valve member, a valve casing surrounding said valve member and having an internally extending hollow cylindrical portion provided with a bore spaced from the open end of said barrel, said valve member having a sleeve portion adapted to overlap the space between the end of said barrel and said hollow cylindrical portion, a source of compressed air, having a passage extending through said barrel externally of said bore and communicating with the interior of said valve member. Y

` k6. In a pneumatic gun, a barrel, a hollow cylindrical valve member slidable externally of said barrel and larger in internal diameter than the external diameter of said barrel, a diametrical step portion in said barrel intermediate opposite ends of said valve member, means for sealing opposite ends of said Valve member engaging said barrel, said barrel `open near one end of said valve member, a valve casing surrounding Ysaid valve member and having an internally extending hollow cylindrical portion provided with a bore spaced from the open end of said barrel, said valve member, having a sleeve portion adapted to overlap the'space between the end of said barrel and said hollow cylindrical portion, a source oi compressed air, having a passage extending through said barrel-externally of said bore and communieating with the vinterior of said valve member, a Sear tendingto hold said valve member in position, whereby said overlapping portion covers the space between said barrel and said hollow cylindrical portion.

'7. In a pneumatic gun, a drical valve member slidable externally of said barrel and larger in internal diameter than the external diameter' of said barrel, a diametrical step portion in said barrel intermediate opposite ends of said valve member, means for sealing opposite ends of said valve member engaging said barrel, said barrel open near one end of said valve member, avalve casing surrounding said valve member and having an internally extending hollow cylindrical portion provided with a bore spaced from the open end of said barrel, said valve member having a sleeve portion adapted to overlap the space between the end of said barrel rand said hollow cylindrical portion, a source of compressed air, having a passage extending through said barrel externally of said bore and communicating with the interior of said valve member, asear tending to hold said valve member in position, whereby said overlapping portion coversAtlfiespace between said barrel andusaid barrel, a hollow cylinhollow cylindrical portion, hold said sear in position said valve member.

8. In a pneumatic gun, drical valve member slidable externally of said barrel and larger in internal diameter than the external diameter of said barrel, a diametrical step portion in said barrel intermediate opposite ends of said valve member, means for sealing opposite ends of said valve member engaging said barrel, said barrel open near one end of said valve member, a valve casing surrounding said valve member and having an internally extending hollow cylindrical portion provided with a bore spaced from the open end of said barrel, said valve member having a sleeve portion adapted to overlap the space between the end of said barrel and said hollow cylindrical portion, a source of compressed air, having a passage extending through said barrel externally oi said bore and communicating with the interior of said valve member, a sear tending to hold said valve member in position, whereby said overlapping portion covers the space between said barrel and said hollow cylindrical portion, a spring tending to hold said sear in position for engagement with for engagement with said valve member, a bullet-seating bolt in saidv hollow cylindrical portion rearwardly of the open end of said bore, adapted to insert bullets into said bore. Y

9. In apneumatic gun, a barrel, ahollow cylin-l drical valve member slidable externally oi saidV barrel and larger in internal diameter ythanthe external diameter of saidbarrel, a diametrical.

.I step portion in said barrelintermediate opposite ends oi said valve member, kmeans for sealing opposite ends of said valve member enga-ging'said barrel, said barrel open near one end of saidrv valve member, a valve casing surrounding saidl valve member and having an internally. extending hollow cylindrical portion provided with ,v va bore spaced from. the open end of said barrel, said valve member having a sleeve portion-adapted to overlap the space between the end of said bar,- rel and said hollow cylindrical portion, a source of compressed air, having va passage extending through said barrel externally ofsaid borev and communicating withl the interior-,of said valve. member, a sear tending to hold saidvalve member in position, whereby said overlapping portion covers the space between said barrelJandsa-id hollow cylindrical portion, a-spring ltending to hold said sear in position for engagement vwith said valve member, a bullet-,seating boltin said hollow cylindrical portion rearwardly of the open end of said bore, adapted to insert bullets into said bore, said sear having a toggle member in, connection therewithand a triggeredapted -to break saidjtoggle'for permitting said valve member to more under diierential air pressure. for exposing the entire open end oiV said bore'or re,- leasing compressed air internally of saidvalve member into said bore and projecting a bullet therethrough.

10. In a pneumaticrgun: ya. barrel having a bore therein; a source. of compressed air; charnber means for storing said compressed air; valve means associated with said Ychamber means,` said valve means being positioned` radiallyadjacent to an inner vend of said barrel;Y means creating a pressure area directly on said valve `means tending to open same for exposing an open rear end of said bore to compressed airv storedin; said chamber means; passage means fonconducting Said @Depressed air. fr0m.,sei.d,0bember means a spring tending to-y a barrel, a hollow cylin-l past said valve means to said open rear end of said bore; spaced sealing means positioned intermediate said valve means and said passage means axially on both sides of said passage means; independent means mechanically engaging said valve means for maintaining said valve means in a closed position; and means to release said independent means.

11. In a pneumatic gun: a barrel having a bore therein; a source of compressed air; a Valve member positioned for slidableV movement along a line parallel to the axis of said barrel and radially adjacent an inner end of said barrel; chamber means for storing said compressed air; means carried by said valve means and adapted to be acted upon by pressure of said compressed said chamber means upon opening of said valve means; spaced sealing means positioned intermediate said valve means and said passage means axially on both sides of said passage means; independent means mechanically engaging said valve means for maintaining said valve means in a closed position; and means to release said independent means.

parallel to the axis of said barrel and radially adjacent an inner end of said barrel; chamber means for storing said compressed air; means References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 843,573 Blomen Feb. 12, 1907 1,234,062 Matz July 17, 1917 1,276,989 Svenson Aug. 27, 1918 1,292,665 Udesen Jan. 28, 1919 1,481,526 Paul Jan. 22, 1924 1,486,215 Zerbee Mar. 11, 1924 2,147,003 Von Kozurik Feb. 14, 1939 2,357,951 Hale Sept. 12, 1944 2,525,082 Sherman Oct. 10, 1950 2,581,758 Galliano Jan. 8, 1952 

